This invention relates to actuating medical devices. In particular, the invention relates to a needle deployment device and to a method of performing a medical procedure.
The invention can be used advantageously in the field of placing suture elements at a surgical site. Accordingly, the invention can be used in the field of suturing vessels, ducts, and the like, in a patient body. The invention can be used in the field of forming sutures in bowel connections, femoral-popliteal artery anastomoses, and the like. It can also be used in the field of trauma closure, and the like. The invention can be used particularly advantageously in the field of suturing blood vessels together during cardiac surgery, for example. Accordingly, the invention can be used during coronary artery bypass graft surgery (CABG), and the like. However, it is to be appreciated that the field of the invention is not to be limited to such uses only, but extends to actuating medical devices in general.
It is often required to connect a vessel, duct, or the like, such as a hollow organ, or blood vessel, or the like, to a target piece of tissue, such as another vessel, duct, or the like. This is especially true in the case of certain types of cardiac surgery, such as CABG surgery. Often during such CABG surgery it is required to connect, or join, one blood vessel to another so that the vessels are joined together to be in fluid flow communication with each other. A joint formed between blood vessels in this fashion is often referred to as an anastomosis.
As is well known, the heart pumps blood through the body. The heart comprises a plurality of muscles which cooperate with one another to cause contractions of the heart thereby to provide a pumping action. The heart requires blood flow to its muscles to provide its muscles with the necessary oxygen, nutrients, and the like, necessary for muscular contraction. It often happens that one or more of the blood vessels which feed the heart muscles becomes diseased and develops a blockage, or becomes occluded, or the like. When this happens, a region of the heart normally fed by that diseased blood vessel can experience a depletion, or interruption, of blood supply. If such a condition is not treated in a timely fashion, the patient may suffer a heart attack with often fatal results.
CABG procedures are often performed to circumvent such a blockage, or occlusion, in a diseased blood vessel, thereby to provide the region of the heart normally fed by the diseased vessel with blood. This procedure normally involves tapping blood from an appropriate blood source, such as a donor blood vessel such as, for example, the aorta, saphenous vein, mammary artery, or the like, and routing the tapped blood to the diseased vessel downstream of the occlusion or blockage. A variety of procedures are currently employed to provide tapped blood downstream of an occlusion, or blockage, in a diseased blood vessel. One procedure involves making use of a graft. In such a case, an end of the graft is typically sutured to an appropriate blood source to be in fluid flow communication therewith and an opposed end of the graft is typically sutured to a side of the diseased vessel to be in fluid flow communication therewith downstream of the occlusion, or blockage. Another procedure involves suturing a side of a healthy vessel to a side of a diseased vessel downstream of the blockage, or occlusion, so that blood can flow from the healthy vessel to the diseased vessel. A joint between an end of a vessel, or graft, and a side of another vessel, or graft, is often referred to as an end-to-side anastomosis. A joint between a side of a graft, or vessel, and a side of another graft, or vessel, is often referred to as a side-to-side anastomosis.
During CABG surgery, a patient is often connected to a cardiopulmonary bypass machine so that the heart can be stopped temporarily, thereby to ease the task of suturing the various grafts, and/or vessels, together. Furthermore, blood vessels, such as the aorta, for example, are often closed, or clamped, so as to interrupt blood flow through that vessel when that vessel is to be used as a donor vessel or blood source.
When CABG procedures are performed on a patient, the patient normally suffers a great deal of trauma. Accordingly, it would be beneficial if such CABG procedures could be improved so as to decrease patient trauma. In conventional CABG surgery, there are at least three factors that affect the degree of trauma suffered by a patient. These factors include: (1) the time the patient spends on a cardiopulmonary bypass machine, (2) the time the patient spends with a clamped blood vessel, such as the aorta, or the like, and (3) the quality of the anastomoses formed between the blood vessels and/or grafts. It is generally recognized that the risk of patient morbidity rises significantly after the patient has been placed on a cardiopulmonary bypass machine for a period of about one hour. Passage of blood through a cardiopulmonary bypass machine tends to damage blood cells consequently causing degradation in blood quality. Accordingly, the longer a patient is subjected to cardiopulmonary bypass, the more the blood cells become damaged and the higher the degradation in the quality of the blood. A complication often associated with prolonged placement on a cardiopulmonary bypass machine, is distal thrombosis. Distal thrombosis can give rise to embolization in the neurovasculature and can lead to the patient suffering a stroke. Accordingly, it would be beneficial if the period a patient spends on a cardiopulmonary bypass machine during CABG surgery could be reduced.
A factor by which the amount of time a patient spends on a cardiopulmonary bypass machine can be reduced is by reducing the time taken suturing the vessels and/or grafts together to form anastomoses. The average time taken to suture two vessels together to form an anastomosis in accordance with traditional suturing methods, is typically about seven to ten minutes. An average CABG procedure can involve the formation of about five anastomoses. Accordingly, the time spent on suturing during an average CABG procedure can be between about thirty-five to fifty minutes. Therefore, since the task of suturing can constitute a major portion of the one hour period, it would be advantageous if the time spent on such suturing could be reduced. By doing so, the time a patient is subjected to cardiopulmonary bypass would also be reduced, thereby reducing patient trauma and the risks of morbidity.
In so-called xe2x80x9coff-pumpxe2x80x9d procedures, patients are not placed on cardiopulmonary bypass machines. Accordingly, the negative effects associated with cardiopulmonary bypass mentioned above are inhibited. However, the task of suturing is made more difficult since the task of suturing is normally then performed while the heart is beating. This can lead to the formation of anastomoses with reduced integrity. Improperly suturing blood vessels and/or grafts together may lead to post operative complications. Incorrect suturing during surgery requiring correction during the surgery, may unnecessarily extend the time taken to complete the surgery.
Suture placement devices have been proposed which enable a surgeon, or the like, to place suture elements in patient tissue without manually holding and manipulating a suture needle, as has traditionally been the case. Typically, this enables suture elements to be placed through vessels quicker than when traditional suturing techniques are used. It has been found that such suture placement devices can be rather cumbersome to operate. In particular, it has been found that approaching a vessel, during CABG surgery, for example, so as to position the device at an appropriate position at which the device can be actuated to place suture elements through the vessel, can be rather difficult. The device can have a plurality of needles, or the like, arranged selectively to advance and retract so as to pass the suture elements through the wall of the vessel. In addition, it can have actuating arrangements for selectively advancing and retracting the needles. Typically, the actuating arrangements and the needles, along with other parts of the device, are mounted on a common body.
It Would be advantageous to provide a suture placement device which is less cumbersome to operate and which is more easily manageable than the suture placement devices currently used. This should enable suturing operations to be conducted with greater accuracy and in a shorter period of time, especially during CABG surgery, whether use is made of an xe2x80x9coff-pumpxe2x80x9d procedure or a cardiopulmonary bypass machine.
According to one aspect of the invention, there is provided a needle deployment device. The needle deployment device comprises a body, a plurality of medical needles displaceably mounted on the body and an actuator on the body, the actuator being actuatable in response to pressurizing a fluid so as to cause the needles to displace relative to the body.
It has been found that by providing such a needle deployment device where the actuator is actuatable in response to pressurizing a fluid, the device can be arranged to approach tissue and to be positioned relative to the tissue more easily than other needle deployment devices. One reason for this is that the device can be of a relatively compact design thereby enhancing its manageability and easing the task of positioning and holding it at an operative position relative to patient tissue, at which position the needles are to be deployed. When the device is used in an application to place suture elements through tissue, such as through a blood vessel wall during a CABG procedure, for example, the enhanced manageability of the device should enable sutures to be formed quicker and more accurately than other suture placement devices.
The actuator may comprise a piston displaceably mounted in a cylinder, the piston being displaceable relative to the cylinder in response to pressurizing the fluid. The needles may be operatively connected to the piston so that the needles displace relative to the body in response to the piston displacing relative to the cylinder. Accordingly, the device can then typically be actuated by pressurizing a fluid source at a remote location and in fluid flow communication with the device, so as to cause the piston of the device to ride in its associated cylinder thereby to deploy the needles.
According to another aspect of the invention, there is provided a medical system. The system comprises at least two bodies and a plurality of needles displaceably mounted on each body. The system further comprises an actuator on each body, each actuator being selectively actuatable in response to pressurizing a fluid so as to cause the needles to be displaced relative to their associated bodies.
According to another aspect of the invention, there is provided a method of performing a medical procedure. The method comprises pressurizing a fluid, actuating an actuator of a needle deployment device in response to pressurizing the fluid and causing a plurality of needles to displace in response to actuating the actuator.
In this way, the medical procedure can be performed by pressurizing a fluid source at a remote location and in fluid flow communication with the device, so as to cause the needles to be deployed by the device from the remote location.